89 Stroker questions....?

[Brett M]

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A local guy around my area has a 4.5 stroker kit that I am looking into buying. The question is, his XJ had an HO motor and I am wondering if all the parts that he has still apply to my Renix block. Below is what he has sent me, explaining what he has.

"the kit is from Speedmotive

http://www.speedomotive.com/ps-147-1...crank-kit.aspx

this kit right here.the only difference is that i have 9.25:1 pistons.i also ordered .40 over rings but the pistons are still stock bore.the crank has already been snouted just needs to be balanced.the cam i bought is a Crane 204/216.i was going to bring the CR to the limit of pump gas which is 9.5 with a jeep 4.0 .i would have came close to getting 245~250 HP


it was roughly based on these options

Option 2: Same as "rockcrawler" except:
Piston dish volume 22cc
9.5:1 CR
Crane #753905 204/216 degree camshaft
2.5" exhaust
Ford 24lb/hr injectors with adjustable FPR or MAP adjuster for '87-'95 engines, Ford 24lb/hr injectors with stock 49psi FPR for '96 and later engines
262hp @ 4800rpm, 325lbft @ 3500rpm

http://www.jeep4.0performance.4mg.com/stroker.html "


I still will have to pick up injectors, as he told me that he doesn't have those yet, and also grab an adjustable MAP sensor, but that's easy enough.


Anyone see anything wrong with this setup? Or should I be okay with picking this up? Any real reason I can't use my RENIX head either?

Thanks for the help
Brett

1989 4.0 Cherokee Laredo

 

[Dr. Dyno]

You can indeed build a stroker to similar specs using the Renix block and head, but with less HP/TQ due to the Renix head's poorer airflow. You could port the Renix head though.
The pistons must have matching rings i.e. stock bore pistons with stock bore rings, +0.040" pistons with +0.040" rings.

 

[Brett M]

You can indeed build a stroker to similar specs using the Renix block and head, but with less HP/TQ due to the Renix head's poorer airflow. You could port the Renix head though.
The pistons must have matching rings i.e. stock bore pistons with stock bore rings, +0.040" pistons with +0.040" rings.

Yeah, I was kind of curious about why he purchased larger rings, but I can always pick those up later on as well. Any reason that the parts would be different between a HO and a Renix or are they all interchangeable?

 

[Dr. Dyno]

The internal engine parts are interchangeable.

 

[Brett M]

The internal engine parts are interchangeable.

Good deal, thanks. Now to pick up an extra block, get the parts together, have the block machined..yeah, all the fun stuff.

 

[MudDawg]

I commonly order the next oversize rings when I build a motor...Eg: +20 pistons....+30 rings....this allows me to fit the rings to the bore for perfect endgap....but using +40 rings for a stock bore motor is too much.

 

[Brett M]

I commonly order the next oversize rings when I build a motor...Eg: +20 pistons....+30 rings....this allows me to fit the rings to the bore for perfect endgap....but using +40 rings for a stock bore motor is too much.

Yeah, I don't think that I'll bore it over anyway. I'll just get some stock rings:repair:

 

[Flash]

I commonly order the next oversize rings when I build a motor...Eg: +20 pistons....+30 rings....this allows me to fit the rings to the bore for perfect endgap....but using +40 rings for a stock bore motor is too much.

I would think that a standered to .020 would cause the ring to set in the bore egg shaped. and Evan .010 could show light between the ring and bore, in places........no?
I have never used more than a .005 over sized ring and the machines shop did the filing.
I haven't us this much over sized of a ring and wondering if you have had good success with it?


Flash.